000
AXPZ20 KNHC 170420
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT NOV 17 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0400 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG AXIS 6N77W 9N84W 7N90W 9N127W 
9N140W. NO SIGNIFICANT CONVECTION. 

...DISCUSSION...

E OF 105W...
AMPLIFIED UPPER LEVEL PATTERN REMAINS IN PLACE ACROSS MUCH OF 
THE UNITED STATES WITH A SHARP NEGATIVELY TILTED TROUGH LIFTING 
NWD OFF THE E COAST INTO THE FAR NW ATLC...AND A SHEARING  UPPER 
LOW CENTERED OVER NEW MEXICO. AS A RESULT...THE UPPER RIDGE OVER 
MEXICO HAS FLATTENED WEAKENED AND EXTENDS NWD INTO LOUISIANA
AND EXTENDS SWD INTO THE WRN GULF OF MEXICO...AND SUBSIDENT AIR 
COVERS MUCH OF CENTRAL/SE MEXICO AS WELL AS THE ADJACENT PACIFIC 
WATERS E OF 108W. A WEAK UPPER LEVEL TROUGH IS NOTED FROM 
GUATEMALA TO THE NICARAGUA/COSTA RICA BORDER AND IS ENHANCING 
SOME CONVECTIVE ACTIVITY NEAR COSTA RICA AND PANAMA. ANOTHER 
TROUGH IS LOCATED ALONG 110W AND 50 KT WINDS ALOFT ARE LOCATED 
JUST DOWNSTREAM MAINLY S OF 10N IN THE DIRECTION OF PANAMA AND 
COLOMBIA.

GALE CONDITIONS ARE WINDING DOWN OVER THE GULF OF TEHUANTEPEC.
THIS EVENINGS QUIKSCAT PASS MISSED THE AREA OF CONCERN...HOWEVER
OBSERVATIONS FROM SALINA CRUZ INDICATED NLY WINDS HAVE DROPPED 
TO 18 KT. WINDS WILL SLOWLY DECREASE THROUGH THE REMAINDER OF 
THE NIGHT AND BE BELOW GALE FORCE BY MORNING. WINDS ARE ALSO UP 
TO 20-25 KT FROM THE GULF OF PAPAGAYO WWD AND SHOULD CONTINUE 
FOR NEXT 36 HOURS OR SO.

W OF 105W...
A SHEARING UPPER LOW IS LIFTING NEWD OVER NEW MEXICO AND THE 
ASSOCIATED TROUGHING IS DRAGGING A SWATH OF DRY AIR/SUBSIDENCE 
EWD N OF 20N INTO EXTREME NW MEXICO. REGARDLESS OF THE DRY 
AIR...THE UPPER LOW IS CAUSING SCATTERED CLOUDINESS WITH 
EMBEDDED SHOWERS ACROSS THE MOUNTAINS OF NRN MEXICO. DUE TO THE 
SUBSIDENCE AND A 1024 MB HIGH NEAR 31N129W...A BROKEN 
STRATOCUMULUS FIELD LIES N OF 23N. FARTHER S...A DEEP CUT-OFF 
LOW HAS DEVELOPED SE OF THE HAWAIIAN ISLANDS NEAR 14N152W AND 
THE SUBTROPICAL JET EXTENDS ROUGHLY ALONG 22N EWD TO WRN 
MEXICO...WITH UPPER LEVEL WINDS OF 55-65 KT. THE UPPER LOW IS 
CAUSING SCATTERED CONVECTION ALONG THE ITCZ W OF 142W...BUT SWLY 
WINDS ALOFT ARE BLOWING COLD-TOPPED CIRRUS INTO THE AREA FROM 
10N-20N W OF 130W AND ADDITIONAL MOISTURE CONTINUING E TOWARDS 
MEXICO.

$$
COBB